I used 01 and tempered at 400 F for 1 hour. I did a test piece a while back and that gave me between 57 and 58 RC. We have a hardness tester at work. The as quenched hardness seemed low @ ~ 62. The blade warped a little, and trying to straighten it, I broke the tip off. Its now a 3" hunter instead of 3.5" but otherwise no big loss. I heat treat with a torch and firebrick setup. I'm pretty sure I heated one side more than the other, and maybe ground it too thin before hardening. I'm out of steel now, and was wondering if I should stick w/ O1, or switch to something and have someone else do the HT for me. I was thinking 440C. Thanks for any advice.